docs: standardize GOVERNANCE.md

[l5io]

Summary

• add the requested root GOVERNANCE.md text
• replace outdated governance stubs with the maintainers reference

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[gemini-code-assist]

Code Review

This pull request introduces a new GOVERNANCE.md file that directs readers to the MAINTAINERS.md file for the list of current project maintainers. The reviewer suggested adding a top-level # Governance heading to improve the Markdown document's structure and presentation.

[gemini-code-assist]

It is standard practice for Markdown documents to start with a top-level heading (H1) to provide context and structure. Adding a # Governance header would improve the document's presentation.

Suggested change

	The current maintainers of the Meshery project can be found in the [MAINTAINERS.md](https://github.com/meshery/meshery/blob/master/MAINTAINERS.md) file in the meshery/meshery repository.
	# Governance
	The current maintainers of the Meshery project can be found in the [MAINTAINERS.md](https://github.com/meshery/meshery/blob/master/MAINTAINERS.md) file in the meshery/meshery repository.